Planar Textile Structure, Especially Tissue

ABSTRACT

The invention relates to a planar textile structure, especially a tissue made of compact yarn based on polyacryl fibers. Said polyacryl fibers are staple fibers that are 40 mm to 70 mm long, resulting in a planar textile structure which has a low pore volume, is provided with advantageous properties, and is versatile.

The present invention concerns a textile fabric, especially a woven fabric, made of compact yarn based on acrylic fibers.

Various properties are required of textile fabrics, depending on the application. The requirements can be especially mechanical, physical, chemical, optical, or haptic in nature. The industry has always made an effort to provide its customers with suitably adapted woven fabric designs for the various applications. This led to a series of woven fabric variants that differed in the underlying type of yarn and/or the type of woven fabric structure and/or the finish. The yarn that is used can be selected according to wishes, for example, with respect to the fiber titer, the staple length and structure (blended yarn, compact yarn). In the context of overall balancing, i.e., an evaluation of the woven fabrics with respect to their technical, economic, and ecological efficiency, the demand arose for a reduction of this great variety of woven fabric variants.

Therefore, the objective of the present invention was to create an improved woven fabric whose characteristics provide it with an advantageous versatility.

This objective was achieved with a textile fabric that has the features specified in Claim 1. This textile fabric is especially a woven fabric made of compact yarn produced from acrylic staple fibers. The compact yarn can consist solely of acrylic fibers or it can be a blended yarn consisting of acrylic fibers and other polymer fibers, with these fibers preferably being present as compact yarns in the blended yarn.

The advantages of the invention are also apparent in fabrics that consist of a blended woven fabric that contains several compact yarns, with at least one of the compact yarns consisting of acrylic fibers.

The fabrics of the invention have a higher density and a very low hairiness, which is important for technical finishing processes. These advantages are realized in a textile fabric with compact yarns in staple fiber lengths of 40 mm to 70 mm, and preferably 60 mm. The resulting, new compact yarn of acrylic fibers of the specified staple fiber length allows better twisting of the fibers, so that a smaller pore volume is obtained. On the other hand, a reduced pore volume results in significantly higher abrasion cycles in abrasion tests on the woven fabrics. Previous compact yarn woven fabrics allowed 100,000 abrasion cycles in the Martindale abrasion test before the woven fabric was destroyed. A textile fabric in accordance with the invention, which consists of acrylic fibers with a staple fiber length of 60 mm, withstood 300,000 abrasion cycles in the same test.

The characteristics of the new, improved woven fabric make it versatile. Standardization is also possible with respect to the woven fabric structure and the finishing of the woven fabric, such as surface effects, coatings, and lamination.

The following examples further explain the invention.

EXAMPLE 1

An acrylic fiber woven fabric consisting of compact yarn 40/13.0 (number of ends per cm/number of picks per cm) contains acrylic fibers with a staple fiber length of 40 mm. The pore volume of the yarn from which the fabric is woven is 10% of the total volume of the yarn. The number of fiber ends F is determined at 0.89 million per defined length and weight of the woven fabric. The woven fabric has a weight of 325 g/m² and a thickness of D=0.80 mm. The measured air permeability is 160 L per dm² per minute. The compact yarn is shown schematically in FIG. 1.

EXAMPLE 2

An acrylic fiber woven fabric consisting of compact yarn 40/13.5 (number of ends per cm/number of picks per cm) contains acrylic fibers with a staple fiber length of 60 mm. The pore volume of the yarn from which the fabric is woven is 4% of the total volume of the yarn. The number of fiber ends is determined at 0.59 million per defined length and weight of the woven fabric. The woven fabric has a weight of 325 g/m² and a thickness of D=0.78 mm. The measured air permeability is 148 L per dm² per minute. The compact yarn is shown schematically in FIG. 2.

EXAMPLE 3

An acrylic fiber woven fabric consisting of compact yarn 40/13.5 (number of ends per cm/number of picks per cm) contains acrylic fibers with a staple fiber length of 80 mm. The pore volume of the yarn from which the fabric is woven is 1% of the total volume of the yarn. The number of fiber ends is determined at 0.48 million per defined length and weight of the woven fabric. The woven fabric has a weight of 325 g/m² and a thickness of D=0.75 mm. The measured air permeability is 120 L per dm² per minute. The compact yarn is shown schematically in FIG. 3.

All three of the examples given here are woven fabrics with a high density, which is a result of the number of fibers in the warp and weft. The thin yarn causes more threads to be present per unit surface area of the woven fabric at the same weight per m². On the other hand, the thread density is also increased by the use of compact yarn, so that the woven fabric has very low hairiness. On the other hand, all three of the woven fabrics described here have a very low pore volume, i.e., the compact yarn consists mostly of yarn and only to a very small extent of pores, specifically 10% in Example 1 and 1% in Example 3. This is achieved by virtue of the fact that the staple fibers of staple fiber length 40 mm to 70 mm are aligned essentially parallel in the compact yarn and twist better. The good ability of the acrylic fibers to bundle allows good compactability during the further spinning process. Previous compact spinning processes of acrylic fibers resulted in nibs, neps, and snicks, so that it was not possible to use the compact spinning process to spin the fibers.

This statement is supplemented by Table 1 below, in which the three woven fabrics mentioned above were tested and scored with respect to their various properties. A woven fabric made of filaments with a length of 20 mm and a woven fabric with staple fibers 100 mm long were included in the table for comparison. The fabrics were rated on a scale of 1 to 5, with 1 being the best rating and 5 the worst. The combined score for all of the properties shows that the properties of the woven fabrics of the invention allow broad use of these fabrics.

A woven fabric of the invention can be processed to advantage into convertible top materials, filter materials, awnings, tarpaulins, and covers for sailboats.

TABLE 1 PROPERTIES OF VARIOUS COMPACT YARN WOVEN FABRICS Staple Fiber Length 40 60 80 100 20 mm mm* mm* mm* mm Mechanical Properties Breaking Strength 4 2 1 1 1 Abrasion Resistance 3 2 1 1 1 Stitch Tear Resistance 4 2 2 3 4 Seam Strength/Slip Resistance 3 2 2 3 4 Crease Resistance 2 2 2 3 4 Flex Crack Resistance 3 2 2 3 4 “Buckling Resistance” 4 3 3 4 5 Cutting/Punching Resistance 4 3 2 3 5 Folding Behavior 2 2 2 2 4 Pilling Resistance 5 4 3 2 1 Mean Score 3.4 2.4 2 2.5 100 Physicochemical Properties UV Resistance 1 1 1 1 1 High-Temperature Light Fastness 2 2 2 2 2 Burning Behavior 4 4 3 3 4 Heat Resistance 3 3 3 3 4 Resistance to Chemicals 2 2 2 2 2 Finishability 3 3 2 2 3 Oil/Water/Dirt-Repelling 4 3 2 2 3 Behavior Mean Score 2.7 2.6 2.1 2.1 2.7 Optical and Haptic operties Constancy of Appearance 3 3 2 1 3 Hand 4 3 1 1 4 Light Protection 2 1 1 1 2 Mean Score 3 2.3 1.3 1.0 3.0 Overall Score 3.1 2.5 2.0 2.2 3.1 *Woven fabrics of the invention 

1. A textile fabric, especially nonwoven fabric, made of compact yarn based on acrylic fibers, wherein the pore volume of the compact yarn accounts for less than 20% of the total volume of the compact yarn and the acrylic fibers are staple fibers with a staple fiber length of 40 mm to 80 mm.
 2. A fabric in accordance with claim 1, wherein the preferred staple fiber length is 60 mm.
 3. A fabric in accordance with claim 1, wherein the compact yarn is a blended yarn that consists of two or more compact yarns, with at least one of the compact yarns consisting of acrylic fibers.
 4. A fabric in accordance with claim 1, wherein the fabric is a blended woven fabric that consists of two or more compact yarns, with at least one of the compact yarns containing acrylic fibers.
 5. The use of a woven fabric in accordance with claim 1 for convertible top materials, filter materials, awnings, tarpaulins, and covers for sailboats. 